the density of 2 molal aqueous solution of NaOH is 1.10g/L. Calculate the molarity of the solution.
2 m means 2 mols NaOH/kg solvent = 40 g NaOH/1000 g solvent = 40 g NaOH/1040 g soln.
d = 1.10 g/mL. Convert mass 1040 and density 1.10 g/mL to volume, change that to L, then 2/L = M
To calculate the molarity of the solution, we first need to convert the given information into the appropriate units.
Density is typically expressed in grams per milliliter (g/mL), so we need to convert the given density from grams per liter (g/L) to grams per milliliter (g/mL).
1 liter is equivalent to 1000 milliliters (mL). Therefore, the density of the solution can be converted as follows:
1.10 g/L * (1 mL / 1000 L) = 0.00110 g/mL
Now that we have the density in grams per milliliter, we can proceed with determining the molarity.
Molarity is defined as the number of moles of solute per liter of solution. Since we are given the density in grams per milliliter, we need to convert it to grams per liter before we can calculate the molarity.
To convert the density from grams per milliliter to grams per liter, we multiply by 1000:
0.00110 g/mL * 1000 mL/L = 1.10 g/L
Now, we can use the molar mass of NaOH to calculate the molarity.
The molar mass of NaOH is the sum of the atomic masses of sodium (Na), oxygen (O), and hydrogen (H):
(Mass of Na) + (Mass of O) + (Mass of H) = (22.99 g/mol) + (16.00 g/mol) + (1.01 g/mol) = 40.00 g/mol
Since we know the molar mass of NaOH and the density of the solution in grams per liter, we can calculate the number of moles of NaOH in the solution using the formula:
Moles = Mass / Molar mass
Moles = 1.10 g / 40.00 g/mol = 0.0275 mol
The molarity is defined as moles of solute divided by liters of solution. In this case, our solution is 2 molal, meaning it contains 2 moles of NaOH in 1 kilogram (1000 grams) of water. Since we have calculated the number of moles (0.0275 mol), we can calculate the molarity as follows:
Molarity = Moles / Liters
Since we have 1 liter of solution, the molarity is:
Molarity = 0.0275 mol / 1 L = 0.0275 M
Therefore, the molarity of the 2 molal aqueous solution of NaOH is 0.0275 M.